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Tech => Tech Help => Topic started by: Spoonman on May 20, 2013, 07:29:13 PM

Title: Final drive
Post by: Spoonman on May 20, 2013, 07:29:13 PM
Howdy all.

Right - so assuming I opt to go with a direct drive arrangement at 5:1, do I need to be concerned about the health of the chain given the drive sprocket (by which I mean the front sprocket [as opposed to the driven sprocket at the wheel itself]) will be running at ~5krpm @ 60mph resulting a chain speed of 37m/sec (120ft/sec)?

By my numbers, and again working off the TL box ratios (similar torque spec so similar chain seems logical), the drive sprocket doesn't hit 5krpm until 10krpm in 5th at the earliest. That put you at ~130mph so it's not exactly what you'd call a steady state condition.

Would a fixed reduction be in order before coupling to the chain final drive do ye reckon?
Title: Re: Final drive
Post by: Richard230 on May 20, 2013, 08:29:07 PM
I can't answer your technical question, but (from everything that I have heard over the years) a front sprocket with fewer than 13 teeth is said to increase wear on both the chain and the sprocket.
Title: Re: Final drive
Post by: Spoonman on May 20, 2013, 09:44:02 PM
yeah, that much I was aware of - I'd be looking towards 14-70 if a primary reduction isn't required.